Control switch



De'c.- 22, 1931. C, T, EVANS' I 1,837,212

` CONTROL swITcH y Filed oci. 28, 1929 7 f -'V LTL 4 1 1f au 1.a 11"1alK l.. E K Z 1 i l I :L E E n E 0. ga l L 18 i I l 4 l I l f '-5 l I IN VEN TOR.

, v ATTORNEY Patented Dec. 22',y 1931 UNITED STATES PATENT oFr-'lcE A jv CLARENCE T. EVANS, F WAUWATOSA, WISCONSIN, ASSIGNOR TO CUTLEB-HAIMHEB,

INC., 0F MILWAUKEE WISCONSIN, A CORPORATION OF DELAWARE n CONTROL SWITCHApplication filed October 28, 1929. Serial No. 402,938.

This inventionrelates to cont-rol switches, and is particularlyapplicable to pilot switches for controlling electric motors.

The invention has among its objects to provide an improved pilot switchwhich is operf able by a shipper rod or rope and is adapted tionalmovement ti make and break an operating circuit for the line switch andto insure establishment of a maintaining circuit for theline switchprior to interruption of the operating circuit therefor.

Another object is to provide a pilot switch of the aforesaid characterincluding a simple, rugged and eicient switch operating "mechanismincluding means for biasing the operating member into extreme positions.

Various other objects and advantages of the invention will hereinafterappear.

The accompanying drawings illustrate an embodiment of the. inventionwhich will now be described, it being understood that the embodimentillustrated is susceptible of modiication without departing from thespirit and scope of the appended claims.

In the drawings, i

Figure 1 is aplan view of a pilot switch embodying the invention, thecover of the enclosing casing therefor being removed and certain partsof the operating'mechanism being broken away.

Figs. 2 and 3 are sectional views lon lines 2-2 and 33 respectively ofFig. 1.

Figs. 4, 5 and 6 are side elevational views of the switch mechanismshown in Fig. 1 illustrating the same in different operating positions,and

Fig. 7 diagrammatically illustrates the circuit connections for thepilot switch.

Referring to the drawings, and more particularly to Figs. 1 and 2thereof the pilot switch illustrated includes a movable contact element1 associated with a terminal device 2 and adapted to cooperate withstationary conta/cts 3 and 4. Terminal device 2 and stationary contacts3 and 4 are mounted upon an insulating base 5 which is fixed to the rearwall of a box like enclosing casing 6 having a removable cover 7, and ashereinafter set forth the contact element 1 is provided with anoperating mechanism 8 which is carried by one of the side walls of saidcasing. l

More specifically, contact element 1 comprises an elongated metalcontact strip 9 having an insulating strip 10 fixed to the upper facethereof. Said contact element is provided with a pair of ellipticalopenings intermediate the ends thereof for receiving pins 11 and 12fixed to base 5,. Pin 11 is associated with terminal device 2, and asbest shown in Fig. 3 said terminal device also includes a terminal plate13 fixed to the front face of base 5 and a spring 14 surrounding pin 11and held under compression between said terminal plate and strip 9 ofcontact element 1. As shown in Fig. 3 terminal plate 13 is provided witha binding post 13a.

In connection with the foregoing it should be noted that spring 14 tendsto move contact element 1 outwardly upon pins 11 and 12 and also servesto electrically connect con- Y tact strip 9 with terminal plate 13. Alsoit should be noted that spring 14 Vprovides a floating support forcontact element 1 and Y permits translatory movement and also angularmovement of said element in a'plane coinciding with the axes of pins 11and 12.

The stationary contacts 3 and 4 are arranged at opposite ends ofbridging contact 1. Cntact 3 cooperates with the underface of contactstrip 9 and the same has a terminal plate 15 associated therewith whichis fixed to the front face -of base 5 and is provided with a bindingpost 15a. As shown in Fig. 3

stationary contact 4 comprises a C-shaped member having its lower legsecured to the front face of b-ase 5. The lower leg of contact 4 isprovided with iii-.binding post 4L and the up er leg thereof cooperateswith the upper face of contact strip 9.

The operating mechanism for bridging Contact 1 includes a rotatableoperating shaft 16 and a pair of L-shaped levers 17 and 18. Shaft 16 isrotatably mounted within a bearing member 19 fixed within an opening inone of the side walls of casing 6. The outer end of shaft 16 has anoperating lever 2O fixed thereto while the inner end of said shaft isixed to one of the legs of lever 17. The other leg of lever 17 isarranged above contact element 1 and engages said element at a pointintermediate terminal device 2 and stationary Contact 4. 'Bearing member19 .is provided with a turned outer surfacel which forms a bearing forlever 18. Lever 18 has one of its legs rotatably mounted upon bearingmember 19 and the other leg thereof is arranged above contact element 1and engages the same at a point to the right of terminal device 2.

As shown in Fig. 2 levers 17 and 18 are provided with downwardlyextending projections 17a and 18", respectively, which are i connecte-dby a tensionspring 21. Each of the extensions 17a and ,18" is providedwith a roller 22 and spring 21 is provided with hookedfend portions forengaging said rollers. Rotation of lever 17 in opposite direc-- tions islimited by apair of projections 17" and 17c thereon which cooperate withopposite sides of a fixed stop 23 secured to the rear wall of casing 6.Rotation of lever 18 in a counterclockwise direction is limited by aprojection 18" thereon which cooperates withA the left side of stop 23.

The function and operation ofthe aforedescribed pilot switch willnow bemore fully described. Figure 2 illustrates the pilot switch in oliposition and as is apparent from this figure spring 21 tends to movelever 17 in a counterclockwise direction and lever 18 ina clockwisedirection. Lever 17 is held lagainst movement beyond the position shownin Fig. 2 by engagement of lprojection 17" with stop 23 and in thisposition said lever holds contact element 1 out of en agement withstationary contact 4 against t e action of spring 14.V Also as isapparent from Fig. 2 lever 18 holds contact element 1 in engagment withstationary contact 3 against the action of spring 14.

Upon movement of operating lever 20 from the off position shown indotted'lines in Fig. 2 to theintermediate. position shown in dottedlines in Fig. 4, lever 17 is` moved in a clockwise direction against theaction of spring 21 to permit 'contact element 1 to'v move intoengagement with stationary contact 4. With the operating parts in thepo# tact 3 against the, action of spring 14.

Upon movement of operating lever 20-in a` clockwise direction slightlybeyond. the

dotted line position shown in Fig.l 4 lever 17 is moved to bring theaxis of spring 21 above the center of operating shaft 16. Spring 21Vthen acts to bias lever 17in a clockwise direction and lever 18- ina.counterc1ockwise direction and the latter lever is lmoved with a snapi shown in-Fig. 5 contact element 1 is held inv engagement withstationary contact 4- by spring 14 and levers 177 and 18 are heldagainst movement under the action of spring 21 beyond the positionsshown, by engagement of their associated projections 17 c and 18" withstop 23.

During return movement of the operating lever 20 from the position shownin dotted lines in Fig. 5 to the intermediate position shown in Fig.. 6lever 18 remains in the position shown in Fig. 6 while lever 17 moves ina counterclockwise direction to disengage contact element 1 fromstationary contact 4.

Upon movement of operating lever 2O be- X yond the position shown inFig. 6 to the position shown in Fig. 2 lever 17 is moved to bring theaxis of spring 21 below the center of shaft 16. Lever 17 then moves witha snap action under the action of spring 21 and returns contact element1 to the position shown in Fig. 2.

The above described pilot switch is connected as shown in Fig. 7 tocontrol an electromagnetic line switch 24. Said line switch provides forconnection of a motor M across a supply circuit indicated by line L--L2and the same is provided with an operating winding 24'a and normallyopen auxiliary contacts 24".

Tho pilot switch is Shown in off position io Fig. 7 'and as hereinbeforedescribed during movement of operating lever 17 from the oif positionshown in Fig. 2 through the intermediate position shown in Fig. 4contact ele- Jment 1 engages contacts 3 and 4. The operattion shown inFig. 5 contact element l disengages contact 3 and remains in engagementwith contact 4 and the line switch is then maintained energized byv acircuit extending through contact 4, contact element 1 andterminaldevice 2 of thep'ilot switch and through` a resistance-Q` andauxiliary contacts 24" of said line switch. Return of thev pilot switchto jo positionv effects interruption of the. maintaining. circuit forthe' line switch without reestablshment ofthe operating circuittherefor.Under low voltageconditibns the line switch-24drops vout and before .the0perating circuit for the line switch can be reestablished it isnecessary `to return pilot switch to off position.

What I claim as new and desire to secure by Letters Patent is:

1. In a switching device, in combination, a movable contact element, apair of stationary contacts associated with said element and located atopposite ends thereof, a spring associated with said element and tendingto move the same into engagement with one of said stationary contactsand out of engagement with thev other of said stationary contacts andoperating mechanism for said contact element including an operating partmovable unidiectionally to permit movement of said contactelement intoengagement y.with said former stationary contact while maintaining thesame in engagement with said latter stationary contact and to thereafterpermit movement of said contact element out of engagement with saidlatter stationary contact while maintaining the same in engagement withsaid former stationary contact.

2. In a switching device, in combination, a plurality of terminalcontact members, a movable contact element adapted tocooperate'therewith to selectively control two circuits, one of saidcontact members being permanently connected to said movable contactelement, and operating means for said movable contact element includingan operating part movable in one direction out of a given off positionto first establish both of said circuits and to thereafter interrupt oneof said circuits while maintaining the other, said operating part beingreturnable in an opposite direction to off position to interrupt saidlatter circuit Without reestablishing said former circuit. l

3. In a switching device, in combination, a movable contact element, aspring device associated with said element and tending to move the samein one direction, a pair of stationary contacts located at opposite endsof said element, and operating mechanism for said contact elementincluding an operating part movable unidirectionally to permit movementof said contact element into engagement with one of said stationarycontacts under the action of said spring device vwhile maintaining thesame in engagement with the other of said stationary contacts and tothereafter permit movement of said contact element out of engagementwith said latter stationary contact with a snap action under the actionof said spring device while maintaining the same in engagement with saidformer stationary contact.

V4. In a control switch, in combination, a movable contact element, aterminal device therefor connected intermediate the ends thereof, a pairof stationary contacts located at opposite ends ofv said contact elementand arranged on o posite sides thereof, and operaating means or saidcontact element including a movable operating member, said operatingmeans acting upon a given unidirectional movement of said operatingmember to first effect movement of said contact e'le- -ment intoengagement with one of said stationary contacts while 'maintaining thesame .in engagement with the other of said stationary contacts, and tothereafter effect move` ment of said contact element out of engagementwith said last mentioned contact while maintaining the same inengagement with said 'rst mentioned contact.

5. In a control switch, in combination, a movable contact element, aspring terminal device for said element located intermediate 7the endsthereof and biasing the same in one direction, a pair of stationarycontacts associated with said element and located on opposite sidesthereof, a movable operating member, and operating connections betweensaid operating member and said contact element which act upon movementof said operating member in one direction to first permit movevvment ofsaid contact element mtoengagement with one of said stationary contactsunder the action of said spring terminal device while maintaining thesame in engagement with the other of said stationary` contacts and tothereafter permit movement of' said contact element out of engagementwith said latter stationary contact under the action of said springterminal device.

6. In a control switch, in combination, Va movable contact element, apair of stationary contacts located at opposite ends of said element andarranged on opposite sides thereof, a spring terminal device for saidelement located intermediate the ends thereof and biasing the sametowards one of said stationary contacts and out of engagement with theother of said stationary contacts, a pivoted operating member operablebetween ven extreme positions to effect movement o said contact elementinto and out of engagement with said first mentioned contact, and meansassociated with said lever and adapted to act upon movement thereof intoits extreme positions to effect movement of said contact ele- Y mentinto and out of engagement with said last mentioned stationary contact.

7. In a control switch, in combination, a movable. contact element, apair of stationary contacts located at opposite ends of said element andarranged on opposite sides thereof, a spring terminal device for saidelement tending to move the same into engagement with one of saidstationary contacts and out of engagement with theother of saidstationary' contacts, a pivoted operatin lever movable between 'venextreme positions to effect movement o vsaid contact element into andout of engagement with said first mentioned contact, a second pivotedlever .movable between given extreme positions for moving said contactelement into and out of engagement with said last mentioned stationarycontact and means for operating said latter lever with asnap action uponmovement of said former lever in its extreme posiscribed my name. 30

tions.

8. In a control switch, in combination, a movable Contact element, apair. of stationary contacts located at opposite ends of said 'elementand arranged on opposite sides thereof, a spring terminal deviceassociated with said element and' biasing the same towards one 'of saidstationary contacts and away from the other ofi-said stationarycontacts, a pivoted operating lever movable between given extremepositlons to move said Contact element into and out of engagement withsaid first mentioned stationary contact, a second pivoted operatinglever movable 'between given extreme positions to move said contactelement into and out of engagement with said last mentioned stationaryContact, and a spring connection lbetween said levers providing foroperation of said last mentioned lever with a snap action upon movementof said first mentioned lever into its opposite eXtreme position andtoyieldingly hold said first mentioned lever in such extreme posi-` tions.y

ln witness whereoL-I have Jheieunto sub- CLARENCE T. EVANS.

